2021/06/25 by Ilhwan Kim, Donghwa Lee, Seongjin Hong +4
Computer Science · Engineering · Physics and Astronomy · #Block (permutation group theory) #Coherence (philosophical gambling strategy) #Coherence theory #Graph #Optical Network Technologies #Optical fiber #Optical path #Photon #Photonics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum optics #physics.optics #quant-ph
paper · pdf · doi:10.1364/oe.436075
published as Optics Express 29, 29527 (2021) · 8 pages, 4 figures
arxiv created 2021/06/25 · openalex created_date 2021/07/05 · openalex publication_date 2021/08/20 · arxiv updated 2021/08/31 · openalex updated_date 2026/08/05
Linear optical multiports are widely used in photonic quantum information processing. Naturally, these devices are directionally-biased since photons always propagate from the input ports toward the output ports. Recently, the concept of directionally-unbiased linear optical multiports was proposed. These directionally-unbiased multiports allow photons to propagate along a reverse direction, which can greatly reduce the number of required linear optical elements for complicated linear optical quantum networks. Here, we report an experimental demonstration of a 3 × 3 directionally-unbiased linear optical fiber multiport using an optical tritter and mirrors. Compared to the previous demonstration using bulk optical elements which works only with light sources with a long coherence length, our experimental directionally-unbiased 3 × 3 optical multiport does not require a long coherence length since it provides negligible optical path length differences among all possible optical trajectories. It can be a useful building block for implementing large-scale quantum walks on complex graph networks.